The sealant dispensing process is an important step in the manufacture of liquid crystal panels. By dispensing a sealant on the periphery of the panel, the color film substrate is bonded to the array substrate and a liquid crystal cell is formed in the panel. The thickness of the liquid crystal cell can be controlled by controlling the dispensing amount of the sealant.
The conventional sealant dispensing apparatus typically includes an injection cartridge having only one outlet. The sealant is applied to the panel via the outlet. In the cell-alignment process, the inner side and outer side of the sealant are exposed to different environments. Specifically, the inner side of the sealant is in contact with the liquid crystal, and the outer side of the sealant is exposed to air or vacuum. Thus, the pressures at both sides are different. This will result in the height of the outer side of the sealant being lower than the height of the inner side of the sealant, and ultimately in an uneven gap around the panel. The uneven gap usually leads to defects such as yellowing, leakage of light, unevenness of luminance (Mura), and the like at the periphery of the liquid crystal panel.